stdlib.h exists but it's not found

Mark81 · 27 Sept 2019, 14:35

I'm trying to compile an existing application in my cross-compile environment.
In the .pro file I added the include path to the actual sysroot:

INCLUDEPATH += /local/STM32MP15-Ecosystem-v1.0.0/Developer-Package/SDK/sysroots/cortexa7t2hf-neon-vfpv4-openstlinux_weston-linux-gnueabi/usr/include/c++/8.2.0/arm-openstlinux_weston-linux-gnueabi
INCLUDEPATH += /local/STM32MP15-Ecosystem-v1.0.0/Developer-Package/SDK/sysroots/cortexa7t2hf-neon-vfpv4-openstlinux_weston-linux-gnueabi/usr/include

in this way some libraries are found (i.e. ssl and bits/c++config.h.
But I get an error here:

/local/STM32MP15-Ecosystem-v1.0.0/Developer-Package/SDK/sysroots/cortexa7t2hf-neon-vfpv4-openstlinux_weston-linux-gnueabi/usr/include/c++/8.2.0/cstdlib:75:15: fatal error: stdlib.h: No such file or directory
#include_next <stdlib.h>

Using the IDE, I went to that line and pressed F2: it brought me to the correct file:

/local/STM32MP15-Ecosystem-v1.0.0/Developer-Package/SDK/sysroots/cortexa7t2hf-neon-vfpv4-openstlinux_weston-linux-gnueabi/usr/include/stdlib.h

It's weird to me because the path is exacly what I've added to the INCLUDEPATH variable.
So, why the IDE can find the file, while the compiler cannot?

aha_1980 · M Mark81 27 Sept 2019, 14:07

@Mark81 said in stdlib.h exists but it's not found:

In the .pro file I added the include path to the actual sysroot:

This is almost never the correct way to do.

You should have an environment-setup script to setup your compiler. These scripts setup different environment variables. These variables must be added to the cross-compile Kit in Creator.

Then it should work.

Regards

Mark81 · wrote on 27 Sept 2019, 14:44

Thanks. I found the script you're talking about. It has a lot of variables. I need to set all of them?

SDKTARGETSYSROOT
PATH
PKG_CONFIG_SYSROOT_DIR
PKG_CONFIG_PATH
CONFIG_SITE
OECORE_NATIVE_SYSROOT
OECORE_TARGET_SYSROOT
OECORE_ACLOCAL_OPTS
OECORE_BASELIB
OECORE_TARGET_ARCH
OECORE_TARGET_OS
CC
CXX
CPP
AS
LD
GDB
STRIP
RANLIB
OBJCOPY
OBJDUMP
AR
NM
M4
TARGET_PREFIX
CONFIGURE_FLAGS
CFLAGS
CXXFLAGS
LDFLAGS
CPPFLAGS
KCFLAGS
OECORE_DISTRO_VERSION
OECORE_SDK_VERSION
ARCH
CROSS_COMPILE

Kent-Dorfman · 30 Sept 2019, 06:51

A couple of things come to mind that you should be aware of:

are you sure you regenerated the makefile after adding the INCLUDEPATH directives?
if so, try switching the order of the INCLUDEPATH directives to search the C headers first, as #include_next works differently than #include
if the inclusion is in your project code, and not in generated code, then replace <stdlib.h> with <cstdlib>, as that is the prefered inclusion for C++ code.

Mark81 · wrote on 30 Sept 2019, 06:51

@Kent-Dorfman

I ran qmake again
I've just do that - same error
unfortunately that include is indeed in line75 of ctsdlib (/local/STM32MP15-Ecosystem-v1.0.0/Developer-Package/SDK/sysroots/cortexa7t2hf-neon-vfpv4-openstlinux_weston-linux-gnueabi/usr/include/c++/8.2.0/cstdlib)

Anyway I agree with @aha_1980 - I guess the right way is to provide the correct environment. But appliying all of those vars it cannot build anything at all (it doesn't find the compiler). So I bet only few of them are mandatory.